IL-10 producing regulatory B cells ameliorated cardiac hypertrophy of viral myocarditis mice / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To explore the mechanism of B10 cell involved in cardiomyocyte hypertrophy following myocarditis, and to develop potential therapeutic strategies.Methods:BALB/c mice infected with Coxsackie virus B3 induced viral myocarditis model. The expression of angiotensin (ANG)Ⅱ and its receptor in myocarditis mice was detected. The changes of B10 cells in the hearts of control mice and myocarditis mice were analyzed by flow cytometry. After losartan was administered to myocarditis mice, the degree of myocardial inflammation was detected by HE staining, the expression of inflammatory factors was detected by ELISA, the myocardial hypertrophy was detected by wheat germ agglutinin (WGA) staining, and the changes of B10 cells in the heart were analyzed by flow cytometry. The levels of cardiac troponin T (C-TNT) and high mobility group box 1 (HMGB1) protein in neonatal mouse cardiomyocytes treated with ANGⅡ and ANGⅡ+ IL-10 were detected. Cardiomyocytes were treated with ANGⅡ, ANGⅡ+ B10 cells, ANGⅡ+ B10 cells + IL-10 receptor antibody and ANGⅡ+ B cells to detect C-TNT protein levels, and Annexin-V/PI was used to detect the apoptosis of cardiomyocytes. Cardiomyocytes were treated with oxidized HMGB1, reduced HMGB1 and disulfide HMGB1, and C-TNT expression was detected.Results:Coxsackievirus B3 infection caused cardiac hypertrophy, high expression of ANGⅡ and its receptor, and transient increase of B10 cells in mice. Losartan treatment blocked the angiotensin receptor, reduced expansion of B10 cells. B10 cells alleviated apoptosis of cardiomyocytes and inhibited the production of HMGB1 induced by ANGⅡ patch by producing IL-10, thus alleviating viral myocarditis and cardiac hypertrophy.Conclusions:B10 cells may play an important role in myocardial protection in myocarditis.